🌡️ Enhanced Fluid Control Thermostat Kit by Derale 15719 Review

Used in place of the thermostatic bypass in the multi-layer oil filter adapter. while it works fine. No problems with leaking on fittings, PTFE paste is applied to the threads.

Derale is great but other project parts I've bought from HAYDEN are absolute cheap junk. DERALE is made in the USA, Hayden is apparently even made in Chinese POW camps at the lowest level. I couldn't believe that two visually almost identical products could be so different. From now on Hayden = dustbin AND Derale = install and use!

Used on Baja Bug air-cooled engines with external engine oil cooler. My oil temp gauge still takes a few miles to register a change (starts at 120F). It doesn't stop going up until it hits 180 and flattens out there as it makes its way through town. Previously, no more than 140 rose in the city. Combined with a large oil cooler fan firing at 200, my oil temp is perfect now. The picture shows brass connectors but I had aluminum connectors. Saves a few ounces.

Instructions don't say so but if you don't want it to leak you'll have to bury the threads on the fittings. Installed oil cooler, same problem. I have used thread sealant and have never had such a severe thread leak. I was careful because both the factory and female threads are aluminum. But after washing the oil off the garage floor twice, I finally put it in a vise and screwed it on to the last thread. Used sealant for the middle threads and some high temp sealant for the last 3 threads.

The addendum says it comes with brass fittings, it comes with 1/2" NPT to 1/2" plastic BARB. I will not be using plastic fittings on my 4L80E gearbox. I have about $3,000 and I refuse to use plastic hardware. I ordered brass fittings. Some people think cool liquid is the best way. The transmission oil has to be warm and some even do without the standard cooler and the transmission runs cold. Gears should work 200° without any problems. I use it on my 1997 GMC Sonoma and don't want the…